Drill-shank and driving member.



0. F1 COLLINS. DRILL SHANK AND DRIVING MEMBER.

Patented Feb. 18, 1913.

UNITED STATES PATENT OFFICE.

CLYDE F. COLLINS, OF NEW KENSINGTON, PENNSYLVANIA.

DRILL-SHANK AND DRIVING MEMBER.

Thls invention relates to drill shanks and the driving members therefor, and more particularly to an auxiliary shankuneniber.

The primary object of my invention is the provision of positive and reliable means, in a'manner as will be hereinafter set forth, whereby thebroken or twisted end of the shankof a drillcan be repeatedly used, thereby increasing the longevity of the drill and producing a momentary saving, espeeiall in large machine shops where a large num er of drills are used.

Another ob]ect of this invention is to producc an improved drilling mechanism, the

ing a drill from slipping or shifting duringdrillv member of which is so constructed as to secure ready and certamengagement with the drill driving member, thereby preventthe operation of the mechanism.

A further object of this invention is to furnish a drill shank with an auxiliary tang member adapted to receive the strains and stresses set up when the drill is driven.

A further object of this invention is to furnish a drill with a set of auxiliary tangs adapted to be successively used when the 'main tangs are twisted or broken.

' A still further object of this invention is to furnish a drill socket and drill with an interlocking member of such a charaete" that it will securely engage within said socket to hold said drill and effectively resist the strain set up in drilling.

With these and other objects in view, the invention consists in certain constructions. and uncertain parts, improvements and combinations to be hereinafter specifically described and then claimed.

Reference will now be had to the draw ing forming apart of this specification,

wherein there is illustrated a preferred em-v bodiment ofthe invention, but it is to be understood that the structural elements are susceptible to such changes and variatlons as fall within the scope of the appended claim. I

Specification of Letters Patent. Application filed June 17, 1911. Serial No. 633,658.

Patented Feb. 18, 1913.

In the drawing :Figure l is aside elevation of the drill socket and drill in accordance with this invention. Fig. 2 is, a verti -al sectional view of the socket showing the drill in side elevation. Figf 3 is a side elevation of the shank of the drill partly broken away and partly in section. Fig. 4 is a front elevation of the same. Figs. 5, (S and 7 are elevations of interlocking members constituting a set, Fig. 8 is'a perspective view of one of the members. Fig. 9 is a perspective view of a modified form of an auxiliary tang, and Fig. 10 is an elevation of a portion of a modified form of tang mounted in a socket.

The reference numeral 1 denotes a tapering driving member or socket having the upper end thereof reduced, as at 2 to provide a tang 3 so that it: may engage with the spin.- die of a drilling machine in the ordinary manner. The drivingmember or socket 1 has a tapering bore 4 extending from the lower end of the member to a point approximately intermediate the ends of said member. said bore having the walls thereof in parallelism with the outer walls of the member. The upper end of the bore is in communication with a tang socket 5 formed by providing the upper end of the member with a transverse oblong slot (3 and'thcn milling the member t'o'establish communication between the here t and the'slot 6.

The reference numeral 7 denotes a portion of the drill having a tapering shank 8 adapted to engage in the bore 4, and the upper end of the shank 8 is reduced, as at 9 to provide a tang 10 adapted to engage in the socket 5 and prevent the shank from rotating within the member 1. The tang 10 ex tends above the lower end .of the slot 6,

whereby a suitable instrument can be placed in the slot (3 and driven between the upper end of the slot and the upper end of the tang 10 to force the shank 8 downwardly and release it sutlioicnt'ly from the member 1, whereby it can be removed.

The (OllHt'lllltlOll just described is that of the present type of driving member and drill. and when indnrate metal is encountered by the drill 7, the tang 10 is often twisted oil of the shank 8 at the reduced portion 5). thereby rendering the drill shank useless for further operation in connection with the driving member. The twisting or breaking of the tang 10 and the shank 8 repeatedly occurs in large machine shops l and a large number of drills are daily rendered useless and a large expense incurred by the replacing of the drills.

To obviate the entire discarding of the drill that has had the tang twisted therefrom, I have devised an auxiliary tang or interlocking member, a set of which can accompany each drill when the same is dis posed of by the manufacturer. The auxiliary tangs or interlocking members vary in size and, the use of each memberentirely depends upon where the tang is twisted. from the drill shank. For instance, after the tang 10 has been twisted from the shank, the shank 8 is placed in a milling machine and the upper end thereof reduced to provide another tangll, the formation of said tang providing oppositely dis osed horizontal shoulders 12 having a ti let 13 with the tang 11. the milling of said tang being performed in the ordinary and well known manner similar to the formation of the tangs 3 and 10. The shank Bwill be milled. a prescribed distance from the lower end of the shankwhen forming the tang 11,

.whereby an auxiliary tang or interlocking member of the prescribed size can be placed upon the upper end of the shank to serve functionally the same purpose as was performed by the tang 10. This auxiliary tang or interlocking member is shown in Figs 5 and 8 and designated 14. The member is tapered and has the lower end thereof provided with a transverse slot 15 to receive the tang 11 and the upper end thereof reduced to provide a tang 16 adapted to fit in the socket 5. The member 14 has thesame taper as the upper end of the shank that was removed to provide the tang 11, whereby the member 14 will represent a prolongation of the shank. In other words, it completes the shank 8 and imparts to the same a size practically the same as the original shank. The slot 15 is out to snugly receive the tang 11, whereby there will be no lost motion between'the member 14 and the shank 8, and when the member 14 and the shank 8 are placed in the socket 5 and the member 1 the walls of the bore 4 firmly brace the member 14 and back up or reinforce the connection between the member 14 and the tang 1]..

'During the operation of the driving mem ber, should a drill equipped with an auxiliary tang have the tang 16 twisted off, the. shank 8 can be quickly removed and another of the members 14 placed upon thetan 11. Should the tang 11 be twisted off 0 the shank 8, the shank and the member 14 can be removed, the shank milled, a prescribed observed that the member 17 is constructed 2 upon thesame principle as the member '14 only it is made. of a greater length to represent a greater portion of the original shank than that represented by the member 14. This same procedure can be taken by again milling the shank 8 to provide another tang 2O and resorting to the use of the member shownm Fig. 7 and designated 21.

It is obvious that should either of the tangs of the'members 14, 17 or' 21 be twisted off of said members that it is only necessary to replace the'member. As the members can be manufactured at an expense comparatively small to that of the drill, it is apparent that the use of a large number of auxiliary tangs or interlocking members can be resorted to before a drill is discarded, but if each member is properly made of stron and durable material, there is less liability of the tangs 11, 19 and 20 being twisted from. the shank than there is of the tangs fitting in the socket 5, consequent-l a drill shank will be maintained under ordinary conditions.

In Figs. 9 and 10 of the drawing-there is illustrated a modification of the invention, wherein the interlocking member has a tang 22 Maltese cross-shaped in cross section and this tang is adapted to fit in a correspondingly cup-shaped socket 23 provided therefor in a driving member. The socket is in communication.with a single slot 25, whereby thetang 22 can be forced from 'the socket 23. This form of tang and socket provides a more positive connection between the driving member and the shank of a drill.

Nhat I claim is A repair member for broken' shanks of drills com )rising a body tapered to conform to the drili shank forming an extension thereof and having a slot in its larger end receiving tang onits smaller end.

In testimony whereof I aflix my signature the tang on the drill shank and having a 'in the presence of two witnesses.

CLYDE F. COLLINS.

shank to which it is to be applied, said body when in position on the drill. 

